The present invention relates to the use of 4-chloro-5-[(4,5-dihydro-1H-imidazol-2-yl)-amino]-6-methoxy-2-methyl-pyrimidine (=moxonidine) and its physiologically compatible acid addition salts for the treatment of myocardial damage secondary to myocardial infarction and for the production of pharmaceutical preparations suitable for this treatment.